Hi A.,
My daughter was diagnosed with Tort when she was 2 months old. Her pedi showed us the stretches to do with her at every diaper change. She, like all the other babies, hated them. When she was 3 months we noticed a little bit of asymmetry beginning, so we started PT. The therapist showed us the same stretches plus a couple more to help control the tightening in her trunk (she was starting to curve her back, too). She had mild plagio which resulted in some mild frontal bossing (her forehead bulged out a little). We were able to fix the plagio and bossing without a helmet. We just propped the side of her mattress up and really encouraged her to sleep on the other side of her head. We also layed her in her crib so that she would have to turn her head the way she didn't want to in order to see out into the room or see her toys.
The PT helped a ton. We only go every couple of weeks and do the bulk of it at home. She is now 6.5 months and doesn't have any remaining tightness. We are now working on strengthing her neck muscles on the other side, which PT is also very helpful for. Her physical therapist has fitted her with a TOT collar (http://symmetric-designs.com/tot-collar-.html) and we hope to have her all straightened out in the next few weeks.
Sorry to go on for so long, but I know how emotional it can be. Even though tort/plagio is mild compared to what several children face, I was in tears over it at times. Give your son's helmet some personality and it will be darling! People notice my daughters collar, but I've never had anyone stare or be rude. Most just ask questions and are really nice about it.
As one final note, I would definitely recommend PT. We hesitated with that decision, too, but I'm so glad we have gone, even if it's just to have someone verify to us that we're doing things right and she is getting better.
Best of luck!